The Top Vegan Side Effects and Symptoms You Can Expect When Going Vegan

The Top Vegan Side Effects You Can Expect When Going Vegan

diet & exercise on being vegan Mar 03, 2016


When we talk about the basics regarding vegan diets and making the transition, it's important to talk about those first few days, weeks and months into going vegan. I know that I personally had so many questions regarding some of the physical symptoms I was experiencing when I went vegan, and this is completely understandable, as with any dietary change, we are bound to experience differences in the way we feel especially those first few weeks as a vegan.

By side effects I'm simply referring to those physical symptoms we might experience as part of the transition to a plant based diet. Feelings in our bodies and minds that will soon find their perfect peaceful place of equilibrium (we also take an in depth look at some of the emotional side effects you might experience when going vegan here).

How to Prepare Yourself for the Transition from Eating Meat to Being a Vegan

Keep in mind throughout this post that if you’re ever feeling overwhelmed while going vegan, and you’re looking for some support when switching to a vegan diet, we guide you every step of the way in our course called The Roadmap, designed to teach you step-by-step, everything you need to know, from vegan nutrition basics, to the social aspects of being vegan, to cooking, prepping, shopping, travel, food substitutions, finding peace in your relationship with food and so much more.

Here's the deal, if we were to start a low carb diet, a low fat diet or any "fill in the blank" fad diet, we would probably experience things like headaches, difficulty going to the bathroom, fatigue, and we wouldn't think twice about these symptoms. Why? Because these are what we would call mainstream diets, a.k.a the Barnes and Noble "filling the shelves" diets. We've heard of them on the news, from the neighbour who tried them and lost weight, so we feel confident that these uncomfortable symptoms are nothing to be worried about and they'll pass eventually (or until we give up on the diet as is usually the case).

Something really strange happens with veganism though, we get this very scary, overwhelming fear that any new symptoms or changes in our bodies are signs that there's something wrong, that we're close to collapsing on the commute home, or that B12 deficiency will kick in, two days into our diet, because we forgot to take our supplement. Same thing goes for the fear of lack of protein on a vegan diet. 

Why does this happen with a vegan diet and not with a more standard over the counter diet? Because they -our family, friends, the media, etc.- have ingrained in our subconscious that we need to be really careful with veganism because it's somehow incomplete.


Is a Vegan Diet Healthy?

Before we get started with the typical side effects you might be experiencing, rest assured that not only can a well-planned vegan diet can be completely nutritious, balanced and fulfil all our nutrient needs, but it can have added benefits when it comes to our health. The key lies in learning a little bit about meeting nutrient needs as a vegan, and keeping these guidelines in mind when building healthy vegan meals and supplementing when needed.

Learning about some of these essential nutrients, and how to find them in their most absorbable form within a vegan diet is important. You can get access to our vegan resource library with all our recommended books, articles, and science based nutrition resources by registered dietitian nutritionists by clicking here.

Going from a Meat-Based Diet to a Plant-Based Diet

I want to ease your mind by telling you that ANY dietary change (especially one as big as going from a standard meat-based diet to a plant-based one), will have effects on your body while it gets used to new foods, especially, because foods in the plant kingdom vary greatly from those in the animal kingdom in one major way: fiber. Our bodies will especially need to adjust to a much higher intake of fiber (a great thing!), but to which our digestive system needs to adapt over the course of the first few weeks or months.

After this first period of adjustment, and keeping in mind those basic nutritional guidelines to make sure you're getting all the nutrients you need, your body will go through so many wonderful changes that your own doctor will be asking you what you've been doing. It might take some tweaking and some adjustments as you go along on your journey, but my hope is that you too will find your little sweet spot, and the ideal balance that is right for you.

Keep in mind that the list I'm sharing with you today are some of the things I personally experienced, or what I've heard from from our students, readers, family and friends who have transitioned into a vegan diet. By no means is this meant as medical or nutritional advice (although I will guide you to those resources here). I simply want to share my experiences and ease your mind if you might be a few weeks into your journey and have been wondering about the physical changes you've experienced. 

This is the mother of all disclaimers...

... only because there is nothing as precious as your body and your health. If any uncomfortable symptoms have you concerned, are lasting too long or not subsiding at all please consult your physician. You can also find a list and directory of doctors and dietitians who have experience with patients who follow this diet in our resource library


What to Expect when you Go Vegan: Side Effects and Symptoms after Transitioning

We're going to talk about poop and other such fun vegan stuff. Don't say I didn't warn you! I will first add a list of the positive and neutral side effects and the negative or most uncomfortable ones, and then we'll have a special moment to talk about three of the ones I get asked about more frequently: pooping and feeling gassy, headaches and fatigue and acne.

Keep in mind that everyone is different, and you may or may not experience any of these symptoms. Some people experience several, some experience none and it's all just smooth sailing.

Regardless, consult your healthcare provider about any physical or emotional changes that are causing discomfort, and always know that you can go through this transition into veganism with the support of a dietitian nutritionist like the ones we recommend in our vegan health resources here.


Some Common Vegan Side Effects or Symptoms when Going Vegan


On the positive side:

  • A sudden rise in energy levels accompanied by feeling the need to be more active physically. I remember I just felt like moving and felt ready and excited about exercising and walking more.
  • More frequent trips to the bathroom. Vegan foods, fruits, vegetables, grains and legumes in particular, are higher in water content, and they are total fiber-rich powerhouses! I've heard from students and readers that used to have days and days of constipation that were suddenly going once a day or more. Yay for frequent pooping!
  • Better smelling body odor. This one was always mind-blowing for me. The way we smell can sometimes change! (The opposite can also be true. More on this below!).
  • A tan-like "glow" on our skin, especially if you're eating a lot of beta-carotene rich foods.
  • Clearer skin (the opposite can also be true... more on that coming up next).
  • Shinier hair and stronger nails.
  • Fewer PMS symptoms.
  • Your tastebuds come to life. By removing animal-based products from your diet, especially dairy, you'll soon experience a boost in the tastes of fresh foods, and your cravings can start to change too, provided that you are eating plenty of meals and dishes that are satisfying to you, and that can easily be swapped in for the foods and dishes you used to love (think of satisfaction in terms of both flavor, texture and mouth feel, and satisfaction of fullness).
  • Odd cravings for foods you had never felt before. I remember getting serious cravings for things like kale, shiitake mushrooms and brussels sprouts when I had never craved these foods before. Probably due to the fact that lots of foods that weren't in your meal repertoire before, are now more of a staple in your diet, and you begin to find your new favorites that you want to experience again and again.
  • Clearer focus and concentration. A feeling of lightness, and a boost in creativity and new ideas. More so related to having a positive mindset when making this change, and the empowerment, excitement and inspiration that comes with making this big positive change.
  • Better performance in sports or physical activities in general, more stamina and endurance.
  • A higher libido.
  • A sense of relief, of doing good, of happiness due to the fact that you're making such a positive change for yourself, the animals and the planet. Greater awareness about the impact we can create and the power we all have on our own health and that of our planet, all of which affect your mental health and well-being.

On the neutral side:

  • Changes in weight: Some people experience weight loss, some people experience no changes in weight, some people experience weight gain. This is one aspect of going vegan that I like to refer to as a neutral side effect since there are so many cultural expectations as to what our bodies should and shouldn't look like. Some of us are meant to be in a smaller sized body, some of us are meant to be in a larger sized body, and both can include health and well being alongside it. When we go vegan, it can happen that since plant-based foods are naturally lower in calories, some people experience weight loss upon going vegan, but this isn't necessarily the case for everyone. Remember, so many things can affect our weight, starting with our genetics, our metabolism, the foods we eat and our activity levels, our hormonal makeup, and our natural set point range when it comes to weight, aka the weight our bodies will naturally lean towards genetically. I talk a lot about weight loss, restriction, dieting and body image in many of our posts and podcast episodes so make sure to check those out if you're struggling with weight loss expectations when going vegan or with body image (you can start with our dieting chronicles series, our bikini revolution series, or our body image series).

On the negative side:

Remember to consult your doctor if you are feeling un-well or if any of these symptoms persist for too long (we're providing great resources and medical directories for vegan friendly doctors and dietitians at the end of this post).

  • VERY frequent trips to the bathroom (more on this below). 
  • Gas and tummy discomfort: Ah yes, if you've been vegan for a while you KNOW what I'm talking about! Gas comes with the territory and it can really throw you off in the beginning. We'll get into some recommendations and details below. 
  • A change in body odor (either positive, or in this case sometimes negative). Weird one right?! This usually clears up quickly, but it's been a common thread between our students.
  • Skin rashes or acne. Although clearer skin can also be a common symptom after going vegan, some people experience acne (like me!). We're talking about what could be one of the culprits below.
  • Trouble sleeping. As with any diet change, a new caloric intake and the types of foods consumed can change your sleeping patterns a bit. I felt completely hyperactive in the beginning, which made me wake up earlier than usual (I wish I still had that superpower now! I would get so much done!).

  • Strong cravings for animal foods: Any change in your diet can produce cravings for familiar foods, and this is especially true about our emotions towards food and the fact that we're changing our habits in such a big way. It's totally normal to miss some of your favorites, but there are so many vegan alternatives out there now that it's hard to not be able to satisfy a craving. Try some new vegan meats or cheeses. Make sure to include meals that are satisfying to you, and remember that a vegan diet is really just the swapping out of an animal-based ingredient with a plant-based one, and that you can make anything vegan to satisfy your tastebuds and stay happy and balanced with your new way of eating. There is no shame in craving old familiar foods, and wanting to replicate some of the textures and flavors within your new way of eating.
  • Feeling hungry more frequently. If you're feeling hungry between meals, please eat! We underestimate how big of a caloric difference plant foods have over the ones we're used to consuming. You might just need to increase your frequency of meals or keep healthy snacks on hand until you find the balance that works for you.
  • Feeling fatigued or experiencing headaches. A common symptom, we'll discuss this one in detail below.
  • Emotional ups and downs, especially as you deal with family or friends who are unsupportive of your lifestyle changes. Find community. Come here. At brownble and especially if you're a member of My Brownble you always have a caring ear and all the support you will ever need on your journey, along with the support of so many others that are going through exactly the same issues as you are. We take an in depth look at some of the psychological and emotional challenges of going vegan in this post and podcast episode, in case you've struggled with difficult emotions, sadness, depression or anxiety after going vegan and you'd like extra support.


Experiencing Frequent Pooping and Gas after Going Vegan

Fruits and vegetables are so high in fiber that they provide us with countless health benefits. Think of fiber as a giant scrub brush that is passing all the way through our digestive system to help move things along. This means that people eating plant-based diets will get a gold star in the pooping department, but I do remember that for me, the first few weeks were NUTTY! I was going to the bathroom really frequently until my body stabilized on its own and got used to the higher intake of fiber. I still go to the bathroom twice as much as I used to in my meat-eating days (and this is awesome!), but an upset stomach is a thing of the past (and I must say that this - stomach pains, gastritis, diarrhea - was a much more frequent occurrence when I was a meat-eater).

When it comes to gas, let me ease your mind that this subsides with time. It really takes a while for your body to get used to the increased intake of fiber, and especially if beans and other legumes are new to your diet. If you're experiencing excess bloating, or a strange sensation in your tummy (the best way I can describe it is a constant feeling of having just had something fizzy to drink), all of this is usually gas, and your body will slowly adapt to digesting these foods.

Keeping a journal will help so much with noticing which foods might be causing the most discomfort. Once you have the culprits, you can try to add these slowly into your diet. This is how I discovered that contrary to common recommendations which insist lentils don't need to be soaked before cooking them, soaking marked a world of difference for me. To this day I can't eat lentils that haven't been soaked, but I never have problems with eating beans! Go figure?!

Experiencing Headaches and Fatigue when Going Vegan

Headaches and fatigue might be a common symptom especially if you aren't eating enough calories.

I've heard this symptom from people who are trying to avoid too many carbs, or are worried about the effects the new diet might have on their weight and so they restrict their intake. As with any diet you try, if you're eating too little your body will respond with these warning signs. Listen to your hunger signals, and if you're hungry, please eat.

Always keep some snacks with you, eat well rounded balanced meals that include protein, carbohydrates and fats, and if you need to, try eating more frequent meals. This is the way I eat (3 main meals and 1 or 2 snacks) and it really makes me feel my best and maintain energy levels. For you, three bigger meals might be the key, or 5-6 smaller meals, etc. Listen to what your body is telling you during, after, and between meals and honor your hunger, remembering that your energy and intake needs might also change from day to day due to differences in activity levels, your hormonal cycle, and more.

Having Acne after Going Vegan

Oh boy can I speak from personal experience when I talk about this side effect. I remember reading books and articles that said that your skin would clear up like magic on a vegan diet. Why then was I suffering from acne when I had never had this issue before in my life?

Thanks to the help of my doctor, I found the secret little culprit. I was taking too high a dose of my vitamin B12 supplement on just a few days, rather than taking smaller doses every day. First let me say this: if you're vegan, you need to take vitamin B12. This is non-negotiable, period. B12 deficiency can lead to severe neurological, metabolic problems and even death, and if there's one vitamin vegans need to take it's vitamin B12 (as well as any person over the age of fifty no mater what their diet is). There are however different ways to take this vitamin. Many people go for a higher dose just a couple of times a week (what I was doing), while others prefer smaller daily doses (what I do now). Don't get me wrong, the majority of people don't have the B12 acne issue. My husband for instance takes a higher dose twice a week and he has never had acne, but I needed to do the daily smaller dose approach. My skin cleared up and I haven't had this problem since. For all the information you need on proper B12 supplementation click here.

Although the lower daily dose of B12 solved this issue for me, any change in diet can cause changes in your hormonal balance and can also be a cause for acne. If your problem persists or you are getting concerned about anything related to your hormonal health, please consult your doctor.


One Final Note, and the Biggest Tip When Going Vegan: Don't Try to be a Vegan Eating Superhero

I've heard of so many people who try to go vegan, sugar free, oil free, gluten free, soy free, and "you name it" free all at the same time.

Such a restrictive and "all or nothing" approach might take you straight to unhealthy territory rather than the health nirvana you probably thought was attainable by attempting something like this.

Please don't try to be a superhero.

By trying to do it all you'll only feel deprived, anxious and like your entire world was been turned upside down. Additional restrictions can also lead to disordered eating and even a more serious eating disorder, they can lead to nutrient deficiencies and more.

Instead, focus on why you are probably here, you want to be vegan or start making as many vegan choices as you can. Make this your focus and then go out and live your life. It is far too precious to spend it worrying or over-obsessing. A vegan diet is actually a very simple thing, and it's full of health giving and body loving foods that you can enjoy just as much as your old time favorites, without the need to continue restricting foods or having a fear over certain foods.

Please know that you can always find a supportive community here. Stop by the comments and say hi. Tell us your story. Join us in The Roadmap, it's the ultimate guide on how to become a vegan, where we help guide you all the way, step by step. This choice you have made is so positive for you, for the animals, and the world we live in, and we'll be with you every step of the way.

When in doubt, read books, watch films, consult the experts and get inspired.


Enjoy our online library of vegan resources with everything from books, to films, to online videos you can watch right now, podcasts, medical directories and health related information on vegan diets and websites.


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